[packagekit] exclude some upgrades

[David Zeuthen]

On Mon, 2007-11-12 at 19:06 +0000, Richard Hughes wrote:
> On Mon, 2007-11-12 at 13:58 -0500, David Zeuthen wrote:
> > On Mon, 2007-11-12 at 18:14 +0000, Richard Hughes wrote:
> > > > Fair enough. packagekit won't be very useful as an update tool in ,
> > > > rawhide then but I can live with that.
> > 
> > I was trying to convey this is a problem with stable releases too. Users
> > install all sort of 3rd party RPM's and given that RPM's has file deps
> > the update can't happen. It's naive to think that this is not a problem
> > with stable releases. Do you disagree?
> 
> Well yes. You're making the user do something clever because the repo
> has done something dumb.

It's plural (multiple repos) and can happen if repos aren't synced.
Happens every day [1] and takes ages to get fixed.

[1] : especially with kmod's which rpmfusion (successor of Livna) will
continue to ship despite that Fedora banned them.

> >  - User tries to update system
> >  - Transaction can't happen
> >  - Some magic in the PacakgeKit yum backend to figure out the biggest
> >    possible set that actually will make the transaction happen (hint:
> >    look at a yum plugin that actually does this)
> 
> Sure. Either we do this in the yum plugin or we handle this in the
> yumBackend.py file.

If it was me, I'd codify all of it in the PackageKit yum backend. 

(In fact, just thinking, I'd also make sure that no plug-ins are loaded
in the yum instance you're using (rational being that it only takes one
bad apple to ruin the batch and you want PK to work flawlessly). Is this
the case already?)

> >  - User is informed of this by PackageKit showing the update list
> >    but with some of the packages unchecked (GtkCheckButton)
> 
> No, if a user can't be applied then it shouldn't be shown in the package
> update list. The update list shows "updateable" packages.

How will the user know that some packages can't be updated then? In the
worst case you'd be leaving the system in a vulnerable state because
some security update can't get through. That would be bad.

> >  - User reviews the checked updates and presses update
> >  - Life goes on
> 
> Except if you've checked the "automatically update" checkbox. Then you
> can't review anything.

In that case we just do the reasonable thing and install as many updates
we can. If you want to upset some UI people provide an option the UI to
tweak that behavior :-)

     David